Skived-fin annular heat sink

ABSTRACT

A skived-fin annular heat sink is manufactured via a skived-fin technology and includes at least one bottom board and a plurality of fins. The at least one bottom board is bended to form a closed-shaped. The fins are extended outwardly from the at least one bottom board, wherein each of the fins has a bending portion for connecting the fin with the bottom board. Hence the skived-fin annular heat sink can be adapted to a chip of PCB with over limited space, and can used to increase the number of fins for increasing the heat-dissipating area between the chip and the heat sink.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a skived-fin annular heat sink, and particularly relates to an erect skived-fin annular heat sink manufactured via a skived-fin technology

2. Description of the Related Art

According to the increase of IC density, too much heat is resulted from chip operation in the information product. Hence the temperature of the chip such as CPU usually exceeds supportable temperature, and the chip and some components near the chip are damaged.

In order to solve the heat-dissipating problem for chips, many users put a heat sink with a plurality of fins on the chip. The heat sink mainly includes an erect rectangular heat sink or an erect annular heat sink. The annular heat sink is usually used to dispose on chips of a PCB, such as interface card. The annular heat sink is manufactured via extrusion, forging, stamping, machine process, powder forming or press forming. However, the fin density is limited by the above-mentioned process method. Hence the number of fins (is about 100 pieces) is hard to be increased and the thickness of the fins cannot be too thin by the above-mentioned process method.

For example, an extruded annular heat sink is usually made of aluminum materials. A process for manufacturing the extruded annular heat sink includes: melting the aluminum materials and extruding the extruded annular heat sink with same cross-sectional shape via an extruded tool. FIGS. 1 and 2 show two top views of two extruded annular heat sinks of the prior art, respectively. An annular heat sink 9 has a circular cylinder portion 91, a plurality of fins 92 extended outwardly from the cylinder portion 91 and a heat-conducting block 93 disposed in a center portion of the cylinder portion 91 for contacting with a surface of a chip. The heat sink 9 is usually made of high heat-conducting materials. Hence, when the temperature of the chip increases, the heat sink 9 is used to absorb the heat from the chip and the heat is conducted to surrounding air via the fins 92.

In FIG. 2, an annular heat sink 9 a is disclosed. The annular heat sink 9 a has an annular cylinder portion 94 and a plurality of thick base fins 95 extended outwardly from the cylinder portion 94. Each of the base fins 95 has a pair of extending fins 96 extended therefrom for increasing the number of extending fins 96 and the heat-dissipating area. However, the number of extending fins 96 is about 100-120 pieces via the above-mentioned process method.

Another way to manufacture the annular heat sink is to bond or weld the fins on the bottom board. Although the above-mentioned method can increase the number of fins and the heat-dissipating area, the fins do not connect directly with the bottom board. Hence the heat-dissipating effect of the heat sink is decreased.

SUMMARY OF THE INVENTION

The present invention provides a skived-fin annular heat sink to increase the number of fins for increasing the heat-dissipating area between a chip and the heat sink. Moreover the skived-fin annular heat sink can be adapted to on a chip of PCB with over limited space.

One aspect of the invention is a skived-fin annular heat sink. The skived-fin annular heat sink is manufactured via a skived-fin technology and includes at least one bottom board and a plurality of fins. The at least one bottom board is bended to form a closed-shaped; and the fins are extended outwardly from the at least one bottom board, wherein each of the fins has a bending portion for connecting the fin with the bottom board.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. Other advantages and features of the invention will be apparent from the following description, drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The various objectives and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which:

FIG. 1 is a top view of an extruded annular heat sink of the prior art;

FIG. 2 is a top view of another extruded annular heat sink of the prior art;

FIG. 3 is a schematic view of a process for manufacturing a skived-fin heat sink via a skived-fin technology according to the present invention;

FIG. 4 is another schematic view of a process for manufacturing a skived-fin heat sink via a skived-fin technology according to the present invention;

FIG. 4A is a schematic view of a process for manufacturing a skived-fin heat sink via a skived-fin technology according to another embodiment of the present invention;

FIG. 5 is a top view of a skived-fin annular heat sink according to the best embodiment of the present invention;

FIG. 5A is a side view of a skived-fin annular heat sink manufactured via the process of FIG. 4A according to an embodiment of the present invention;

FIG. 5B is a side view of a skived-fin annular heat sink manufactured via the process of FIG. 4A according to another embodiment of the present invention;

FIG. 6 is an across-sectional view along a line 6-6 of a skived-fin annular heat sink in FIG. 5;

FIG. 6A is an across-sectional view of a skived-fin annular heat sink connected with a heat-conducting block according to another embodiment of the present invention;

FIG. 7 is an across-sectional view of a skived-fin annular heat sink according to the second embodiment of the present invention;

FIG. 8 is a top view of a skived-fin annular heat sink according to the third embodiment of the present invention; and

FIG. 9 is a top view of a skived-fin annular heat sink according to the fourth embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 3 shows a schematic view of a process for manufacturing a heat sink via a skived-fin technology according to the present invention. The present invention provides a skived-fin heat sink that is manufactured via a skived-fin technology. The skived-fin technology is the best-developed technology in all heat sink processes. A process for manufacturing the skived-fin heat sink includes providing a plane workpiece 1 firstly. Afterward, the workpiece 1 is fixed on a jig 2 via a calculating angle, and a predetermined front side of the workpiece 1 is shaped via a shaping tool 3 of a punching machine, a milling machine or a special machine such as a CNC according to a carpenter shaping principle. Thereafter, the workpiece 1 is shaped continuously to form a plurality of sheet-shaped fins 11 that do not break away from the workpiece 1, and the sheet-shaped fins 11 are vertical relative to the workpiece 1 to form a plurality of corresponding bending portion 112 via a suitable method. Each of the bending portions 112 is connected between the corresponding sheet-shaped fin 11 and the workpiece 1. Because the fins 11 are integrated on the workpiece 1 via the corresponding bending portions 112 and there is no any joint between the fins 11 and the workpiece 1, there is no any interface or thermal resistance between the fins 11 and the workpiece 1.

FIG. 4 shows another schematic view of a process for manufacturing a skived-fin heat sink via a skived-fin technology according to the present invention. There is just a little bit distance between two sheet-shaped fins 11. Afterward, an end section 13 of the workpiece 1 is cut to form a skived-fin workpiece that has different length according to different embodiment. Finally, the skived-fin workpiece is bended to form a skived-fin annular heat sink by a bending tool.

FIG. 4A shows a schematic view of a process for manufacturing a skived-fin heat sink via a skived-fin technology according to another embodiment of the present invention. The workpiece 1 is fixed obliquely on the jig 2. The workpiece 1 is shaped continuously to form a plurality of sheet-shaped fins 11 a oblique to the workpiece 1. An inclination θ between the sheet-shaped fin 11 a and the workpiece 1 is determined according to an included angle θ between the workpiece 1 and the tool 2. If the workpiece 1 connects to the tool 2 via the included angle θ, the sheet-shaped fin 11 a connects to the workpiece 1 via the inclination θ. Each of the sheet-shaped fins 11 a obliquely tends to one side of the workpiece 1. Finally, the skived-fin workpiece is bended to form a skived-fin annular heat sink with spiral fins by a bending tool.

FIGS. 5 and 6 show a top view of a skived-fin annular heat sink according to the best embodiment of the present invention and an across-sectional view along a line 6-6 of a skived-fin annular heat sink in FIG. 5, respectively. The best embodiment of the present invention provides a closed skived-fin annular heat sink 4. The skived-fin annular heat sink 4 has a plurality of sheet-shaped fins 44, an annular bottom board 42, a plurality of bending portion 442 and a slot 46. The bottom board 42 is an erect closed cylinder. The sheet-shaped fins 44 are connected with the annular bottom board 42 via the corresponding bending portion 442. The skived-fin annular heat sink 4 of the present invention has a larger heat-dissipating area and a good heat-dissipating effect than that of the heat sinks 9, 9 a of prior art according to the above-mentioned processes. Furthermore, a heat-conducting block 5 is disposed in a center portion of the skived-fin annular heat sink 4 and connected to a chip 6 for conducting heat from the chip 6 to the skived-fin annular heat sink 4.

FIG. 5A shows a side view of a skived-fin annular heat sink manufactured via the process of FIG. 4A according to an embodiment of the present invention. The present invention provides a skived-fin annular heat sink 4′ according the FIG. 4A. The skived-fin annular heat sink 4′ has a plurality of oblique fins 44′ arranged thereon in order. Each of the fins 44′ has an upward and oblique angle formed on a bottom side thereof to provide larger spaces for more airflows fluently flowing to a surrounding of the chip 6 via the larger spaces. When airflows blow downward to the surrounding of the chip 6 via a fan, the airflows become oblique and downward airflows via the oblique fins 44′ at the same time. The oblique and downward airflows can improve air trap that is happened by vertical airflows. Hence the skived-fin annular heat sink 4′ of the present invention has a good heat-dissipating effect.

FIG. 5B shows a side view of a skived-fin annular heat sink manufactured via the process of FIG. 4A according to another embodiment of the present invention. A skived-fin annular heat sink 4″ with a plurality of oblique fins 44″ is disclosed. In this embodiment, a parallelogram workpiece is provided to the process of the FIG. 4A.

FIG. 6A shows an across-sectional view of a skived-fin annular heat sink connected with a heat-conducting block according to another embodiment of the present invention. In this embodiment, the present invention provides a taper heat-conducting block 5′ and a skived-fin heat sink 4″ having a plurality of fins 44″ and a taper bottom board 42. Moreover, The skived-fin heat sink 4″ has a receiving space formed in a center portion thereof for receiving the taper heat-conducting block 5′.

Because of the skived-fin heat sink is manufactured by a skived-fin process, the skived-fin heat sink can be made of an aluminum material, an aluminum alloy, a copper or a copper alloy. In the best mold, the skived-fin heat sink 44 is a rectangular shape. However, the shape is not used to limit the present invention. FIG. 7 shows an across-sectional view of a skived-fin annular heat sink according to the second embodiment of the present invention. A skived-fin heat sink 4 a has a bottom board 42 a, and a plurality of trapezoid fins 44 a connected with the bottom board 42 a for increasing the heat-dissipating effect. The fins can be any shapes. For example, when two end triangle portions of the workpiece are cut, the trapezoid fins 44 a can be obtained. Hence, the shape of the fins can be a fan-shaped or an arc-shaped according the different cutting methods.

A heat-conducting block 5 a is received in a center portion of the skived-fin heat sink 4 a. The heat-conducting block 5 a has an exposed bottom edge 52 a extended outside the skived-fin heat sink 4 a for abutting against a bottom side of the bottom board 42 a. Hence, the exposed bottom edge 52 a can provide a larger heat-conducting area for increasing the heat-dissipating effect between the heat-conducting block 5 a and the skived-fin heat sink 4 a.

FIG. 8 shows a top view of a skived-fin annular heat sink according to the third embodiment of the present invention. The present invention provides a process for manufacturing a semicircular skived-fin heat sink 4 b. The semicircular skived-fin heat sink 4 b has two sides connected with two sides of another semicircular skived-fin heat sink 4 b, respectively. Each semicircular skived-fin heat sink 4 b has a bottom board 42 b and a plurality of fin 44 b. Every two bottom boards 42 b can be assembled together to form a closed-shaped. Hence, the present invention can use two semicircular skived-fin heat sink 4 b or more than two fan-shaped skived-fin heat sink 4 b assembled together to form a skived-fin annular heat sink. The third embodiment of the present invention can reduce the difficulty of bending the workpiece 1, and provide a connecting component disposed between two adjacent sides of the skived-fin heat sink. For example, two connecting components 7 b with clamping function are disposed in a slot 46 b for connecting and fixing two adjacent end sides of the semicircular skived-fin heat sink 4 b. Furthermore, the two the semicircular skived-fin heat sinks 4 b can be assembled together via welding or rivet joint.

FIG. 9 shows a top view of a skived-fin annular heat sink according to the fourth embodiment of the present invention. In this embodiment, the present invention provides a rectangular skived-fin annular heat sink 4 c having an erect closed rectangular bottom board 42 c and a plurality of fins 44 c extended outwardly from the bottom board 42 c. Furthermore, the rectangular skived-fin annular heat sink 4 c is easy to manufacture than circular skived-fin annular heat sink, and a heat-conducting block 5 c has a contact area same as a top surface of a chip for increasing effective heat-dissipating area.

Conclusion, the present invention has some advantages, as following:

1. The skived-fin annular heat sink of the present invention has a plurality of sheet-shaped fins more than that of the prior art and a bottom board connected with a center portion thereof for increasing more heat-dissipating area and good heat-dissipating effect;

2. The skived-fin annular heat sink can be made of an aluminum material, an aluminum alloy, a copper or a copper alloy easily; and

3. The skived-fin annular heat sink can be adapted to a chip of PCB with over limited space, such as chips on an interface card. Moreover, a fan can be disposed on the skived-fin annular heat sink for increasing heat-dissipating effect.

Although the present invention has been described with reference to the preferred embodiments thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have been suggested in the foregoing description, and others will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims. 

1. A skived-fin annular heat sink manufactured via a skived-fin technology, comprising: at least one bottom board bended to form a closed-shaped; and a plurality of fins extended outwardly from the at least one bottom board, wherein each of the fins has a bending portion for connecting the fin with the bottom board.
 2. The skived-fin annular heat sink as claimed in claim 1, wherein the bottom board and the fins are made of copper or copper alloy materials.
 3. The skived-fin annular heat sink as claimed in claim 1, wherein the bottom board and the fins are made of aluminum material and aluminum alloy materials.
 4. The skived-fin annular heat sink as claimed in claim 1, wherein the closed-shaped bottom board is formed via two semicircular bottom board or a plurality of fan-shaped bottom board assembled together.
 5. The skived-fin annular heat sink as claimed in claim 4, further comprising at least one connecting component for connecting every two adjacent semicircular bottom boards or fan-shaped bottom board.
 6. The skived-fin annular heat sink as claimed in claim 1, wherein the at least one bottom board is bended to form the closed-shaped via a welding.
 7. The skived-fin annular heat sink as claimed in claim 1, wherein the bottom board is an erect closed cylinder.
 8. The skived-fin annular heat sink as claimed in claim 1, wherein the bottom board is an erect closed rectangle.
 9. The skived-fin annular heat sink as claimed in claim 1, wherein the fins are arranged to form a rectangular or trapezoid shape.
 10. The skived-fin annular heat sink as claimed in claim 1, further comprising a heat-conducting block disposed in a center portion of the bottom board.
 11. The skived-fin annular heat sink as claimed in claim 10, wherein the heat-conducting block has a trapezoid-shaped cross-sectional.
 12. The skived-fin annular heat sink as claimed in claim 1, wherein the fins are arranged obliquely on the bottom board, and each of the fins has an upward and oblique angle formed on a bottom side thereof.
 13. The skived-fin annular heat sink as claimed in claim 1, wherein the fins are arranged spirally on the bottom board. 